Field
Embodiments of the present disclosure generally relate to a process and system for the stabilization of crude. More specifically, embodiments described herein relate to methods and apparatus for stabilizing crude oil components which may be hazardous during handling, storage, and/or transportation.
Description of the Related Art
A process for the stabilization of crude products generally consists of bringing crude oil at a well outlet to API standards, while substantially removing lighter hydrocarbons therefrom. Maximizing the production of crude oil which does not degas, limiting losses of light hydrocarbons, and obtaining a stabilized crude product for safe transportation is highly desired. Although bulk separation of oil, water, and gas occurs in the field, the resulting liquid often retains high quantities of light ends, resulting in a high vapor pressure or RVP. For transportation, further stabilization (e.g., to a lower vapor pressure) may be required to remove soluble light hydrocarbons from the crude.
Conventional small field stabilization units, often referred to as “heater treaters,” can be used to stabilize crude for transportation, but these units are inefficient. Conventional stabilization units utilize high amounts of energy to operate and fractionate poorly, as more light material must be removed from the crude oil to meet the same vapor pressure specification. There is an incentive to minimize the amount of light material removed from the crude (i.e., minimize the shrinkage) because that material must then be sold at a discount. Minimizing shrinkage provides more stabilized crude oil available for sale at full crude price.
Conventional stabilizer columns are more efficient than field heater treaters and operate at and/or maintain crude products therein at pressures of about 150 psig, top temperatures of about 250 degrees Fahrenheit, and bottom temperatures of about 350 degrees Fahrenheit. To process crude feeds containing salts, such high temperatures require the use of a desalting system, as temperatures above about 350 degrees Fahrenheit hydrolyze feed chlorides. Hydrolyzed feed chlorides form acids that corrode equipment.
Therefore, there is a need for an improved crude stabilization system which maintains low process pressures and temperatures, reduces product shrinkage, and provides a stabilized crude product for safe transportation.